Undernatural
by Higher on Fire
Summary: When Sam and Dean fall into Mt. Ebbott on the search for a lost child, they encounter several new beings. A demonic flower, a friendly goat lady, and even some weird skeletons. Sam and Dean have plenty of fun trying to find their little friend, but when they learn the true secrets of the Underground, they realize their search is more desperate than they though.
1. Your Best Friend

**Hello citizens of the Underground! As you can probably tell, I'm going to be writing a Undertale/Supernatural crossover! WOAH! WHY SO MANY NEW STORIES? Because I'm trash, that's why. Anyway, here's my newest story. I hope you love it. Check out some of my other stories if you'd like. Also, this is set shortly after the last episode of season 1 ^.^ BBY SAM AND DEAN! Sorry, got excited, you know. Anyways, Thanks and Enjoy.**

 **Mt. Ebbott - Present Day**

Sam looked over the edge of Mt. Ebbott, staring into the deep abyss.

"Dean, anyone who goes down there never comes back."

His brother patted his back as he walked up behind him. Dean stood, looking down with his brother, his confidence in them beginning to show.

"Oh, come on, Sammy! Since when have we been scared of a little adventure? Besides, I got a call saying a kid fell down here about a day and a half ago. You think they survived it?" Dean ended his question with a quick glance at Sam as he grabbed a pile of rope from near a tree and began to tie it up.

Sam shook his head, turning to help his brother, but tripping as he did so.

"Dean!"

He shouted as he felt the unfamiliar weightlessness of falling, hearing Dean go down behind him. He was sure he was going to die, and his last thought was of Dean before he hit the ground.

 **Hours Later**

His head was thumping, and someone rocked his shoulder. "Sammy? Oh God, Sammy. Wake up!"

Sam blinked, slowly opening his eyes in the light from the hole from above.

"We lived?"

Dean nodded, helping his brother up. They gave each other a look, knowing that they should explore the place together. They followed a narrow tunnel to a large entryway.

"Howdy, I'm Flowey! Flowey the Flower!"

Dean and Sam stared at each other in equal horror as a flower sprung from the ground out of nowhere. His petals were yellow, surrounding a white center. He wore a big grin on his face, which Dean wanted nothing to do with.

"Um, hey there. We're a bit lost. W-what...? Where are we?" Sam questioned.

Dean shot him a look, "Dude, don't talk to that thing!"

Sam shrugged as Flowey continued on.

"You're new to the Underground, aren'tcha?"

Sam and Dean gave each other a final look before deciding to play along.

"Sure...I guess. Is that where we are?"

"Sure is! You two must be pretty confused. Someone ought to teach you boys how things work around here. I guess little old me will have to do."

Dean and Sam felt themselves be lifted from the ground, two heart shapes floating in front of them. Sam's was a bright, red heart and Dean's shown orange in front of them.

"These are your SOULS, the very culmination of your beings," Flowey's voice squeaked cheerfully.

Dean cut in, "Hey, could you put us the hell down? I don't like my soul being messed with, buddy."

Flowey shot him a harsh look, before continuing as if nothing had happened. "Your soul starts out weak, but grows stronger if you gain LV. That stands for LOVE." He gave a little wink before continuing. "Down here love is spread through little...white...FRIENDLINESS PELLETS!"

Dean's face contorted showing his disgust for the cheer and gross, fake smile plastered on the flower's face.

Dean began to shout, "Cut the crap, pipsqueak. I ain't going anywhere near your damn 'friendliness pellets'Now put me the hell down or I swear to Go-"

Out of nowhere a ball of fire struck the flower, sending him flying into the darkness.

"Hello, my...children? You don't look very young."


	2. Toriel, Caretaker of the Ruins

**Hey all! I finally posted these two chapters (after having them sit in my folders for literally 3 months) because fanfic user Tc the writer reminded me that I had this story. Anyway, sorry for the wait and without further ado, here's chapter two of the story! Thanks and Enjoy!**

The voice came from a tall, horned humanoid goat. She towered over even Sam, who was a giant. She wore a set of purple robes over a white dress. Pure white fur covered her body, her light pink nose and red eyes the only color to her body. She looked like a mother or kindergarten teacher, her eyes showing no malice or hatred, but also full of motherly secrets.

Dean felt oddly at ease with the newcomer, though it was Sam's turn to be suspicious this time. She had called them children, though seemed to know that they were not. Her eyes were not only red in the iris, but bloodshot, and the fur around them was soaked with tears. She had been crying, but putting on a happy face to keep the boys comfortable.

"I am Toriel, caretaker of the Ruins. It is so strange, to see another human. Not just one, either, but two. What are you doing, so far from your home?" Toriel asked.

Her voice was quiet and steady, not wavering or firm. She kept a certain level of confidence and [evenness] to her voice when she spoke, as if she knew that she would be the boys' best shot.

Dean spoke first, "I'm Dean, and this is my younger brother Sam. We were coming to rescue a child who fell down here, but we tripped when we were preparing the rope to propel down here. Have you seen any human children come down here, lately?"

The goat-woman sniffed, suddenly stiffening as he mentioned the fallen child. More tears came to her eyes, and she fell as a wail escaped her lips.

Dean took a step back, taken by surprise at the woman's sudden loss of composure.

She sniffed, sobbing between words. "A human child fell down here not long ago. I let them leave the Ruins. You are too late, they are long dead by now. They always do this to me. They fall. They leave. They die. The king of our kind, Asgore, has probably already sent one of his royal guard to kill them."

Dean shot a quick glance at Sam before kneeling to meet this woman's height. She glanced up at him, then rested her head on his chest. Dean's face flushed instantly, the warm weight on his chest sparking an unusual self consciousness in his chest.

"We'll find the kid. As soon as we do, we'll let you know. I'll help you find them. I can tell that you really care for them. We'll get them back. I promise," Dean whispered to her.

The woman nodded, quietly thanking Dean as he helped her stand. She lifted her head, a new look of DETERMINATION in her eyes.

"Follow me. I will show you the entrance to the Underground. I must ask you to be careful. I want all of you to escape here with your SOULs. Please, make sure that I see you all again."

With that thought, she turned, leading them deeper into the ruins.


	3. Leaving Home

**Hey all! I'm so glad to FINALLY by updating this story. I gave you guys two chapters in one go and, hopefully sometime soon, I'll be posting even more updates. Let me know through PM's what you guys want me to update next, along with this story. Thanks and Enjoy.**

Dean and Sam stood in the living room of Toriel's home, sighing with the warmth of the fire. She had disappeared into the kitchen, heading off to grab food for their journey underground. They both told her that they packed plenty for the trip, which was true, but she insisted. It was only after Toriel left that Dean had realized that all of their food was still by the hole in the mountain. He hadn't grabbed his pack when he went after Sam. He thanked Toriel silently for being so persistent.

Toriel returned, carrying two floral packs of food and new scarves. She wrapped each boy tightly in their scarves, which matched their shirts, and helped them put on their bags.

"I made sure you had plenty of food. Spider doughnuts, from the bake sale just outside, cinnamon butterscotch pie, and some fresh fruits. Make sure to keep your HP maxed out before any battles that may ensue." She kissed them both on the top of the head.

She lead them to the stairs to the basement, refusing to go any farther. Dean and Sam descended the steps, which ended in a long, dim hallway. At the end of the hall sat a heavy wood door with an odd symbol carved into it. It was the same symbol that Dean had seen on Toriel's robes. He pushed the door open tentatively, and was met with the same room at the beginning of the Ruins. Flowey sat in a patch of grass just before their exit.

"I bet you think you can save them, don't you? Well, Chara isn't going to make it through the Underground, and neither will you."

Dean rolled his eyes, walking straight passed the flower and into the Underground, Sam close on his heels. They reached a small bridge, just outside the forest, when Dean and Sam heard the footsteps behind them. They both stopped, waiting to see if whatever it was would follow.

More footsteps. The being was only two feet behind them. There was silence, the stillness in the air was chilling. Sam clutched the scarf around his neck, trying to draw strength from its warmth. Dean reached for the knife in his pocket, only to realize he'd left it behind at the top of the mountain.

" S." A voice rang out behind them. "DON'T YOU KNOW HOW TO GREET A NEW FRIEND? TURN AROUND AND SHAKE MY HAND."

Dean turn first, followed by Sam. The figure was cloaked in shadows, the hood of his hoodie blocking his face. Dean reached out and grabbed a boney hand, firmly grasping it.

Silence, until…

PFFFFFFFT!


End file.
